This invention relates to a surgical stapling apparatus, and more particularly to a surgical stapling apparatus for effecting closure of circular anastomosis.
A colon resection operation involves removing a section of the tubular colon which has become diseased and then joining the ends in an end-to-end anastomosis ("EEA"). Approximately 100,000 colon resections are performed each year in the United States, 70% of which are distal to the right colon. Although gastrointestinal anastomosis ("GIA") stapling devices are available for some colon resections, most surgeons do not use such devices to create left sided colonic anastomosis, and only about 15% of colon anastomosis are within reach of the existing EEA devices through the rectum.
Various types of circular anastomosis stapler devices are available for effecting end-to-end circular anastomosis stapling. Examples of such devices are described in U.S. Pat. No. 4,752,024, U.S. Pat. No. 4,485,817 and patents cited therein. Such stapling devices typically comprise a fastener holding assembly and an anvil assembly located at the distal end of a stapling mechanism, with means to control the spacing distance between the anvil assembly and fastener holding assembly. During surgical operations, when a surgeon desires to join by stapling two ends of tubular tissue, such as a colon in a colon resection operation, the device is inserted through the colon so that the cut between the two colon sections is disposed in a space between the anvil and stapling mechanism. Purse string-like sutures are made in both colon ends with the sutures pulled tight. A mechanism then pulls the anvil and the stapling mechanism together whereby one or more staples effect an annular stapling function, and a circular cutting blade disposed radially inwardly of the annular stapling array cuts out the remaining tissue radially inwardly of the annular staple ring. The apparatus is then removed from the colon, leaving a clean cut line and an annular array of staples holding the two previously unjoined colon portions together.
While the above-described devices have been effective for making end-to-end anastomosis, many of these devices suffer from disadvantages. Many of the available devices have a rigid structure which preclude their application for other than straight intestines. Some of these devices additionally suffer from a disadvantage in that anastomosis may be effected only for a limited distance from the entrance cavity, such as the rectum. While some of these devices have employed flexible structure such as a flexible sheath or tube to enable their application to curved intestines, such devices do not provide means for steering the device through a curved section of an intestine, or to branch the device to a selected one of two or more branches in an intestine. Further, these devices also fail to provide means for viewing the surgical site or an interior human cavity on route to the surgical site.